Prefer trailing dots over leading dots

[amiel]

The community styleguide did not pick one and instead encourages teams to pick one.

There is a lengthy discussion here: rubocop/ruby-style-guide#176 and is a pretty interesting read.

Note that this only applies to ruby.

What are we talking about?

To clarify, here's what we're talking about:

  # trailing dots
  one.two.three.
    four

  # leading dots
  one.two.three
    .four

My argument

Having read through the discussion, I propose we use trailing dots.

It seems like the arguments can be oversimplified to mostly (source:

• leading dots is more visually pleasing
• trailing dots has more functional advantages

Here are some of the arguments I like:

• Basically, when continuing lines like this, you need context on both lines. Using the trailing dot gives context on the first line, indentation gives context on the second line (source).
• Code written with leading dots cannot be pasted in to irb/pry (source).
• Loading dots are easier for parsers (source).
• There are some scenarios in which leading dots can cause bugs (source).

[amiel]

I'd love input from everyone on this, but will specifically wait for review from the people that use ruby the most ( @kyle-rader and @nathancarnes ).

[kyle-rader]

@amiel @nathancarnes I agree with trailing dots.
I think the summary of arguments from @amiel is pretty good, but this guy adds some more points

Notably, that leading dots don't even work in Ruby 1.8, and there is an actual performance penalty.

[nathancarnes]

Works for me.

But, more broadly: do not do either except in rare cases. It's probably an indication you have a terrible, terrible Demeter violation.